Need help to kill star base

I am TEC

Lots of bombers or the TEC Ogrov antistructure cruiser is your best best. Avoid attacking upgraded starbases with other units unless you have no choice. Both of those units can attack from outside the starbase's range, so just use your fleet to protect them while they take out the starbase.

But beware of the Orkulus.... it can move.... so either you have quite a lot Orgrovs to kill it quickly or it kills them.

Indeed the AI use moving upgraded starbases.  I have read in Starbse 101 this steps:

1) kill  fabricators

2) bombar planets

3)kill repair bays

4) kill constructors regenerators

5) kill starbase

The starbase is so strong that it kills all my fleet when i tried to follow the above steps.  So, i may try killing the Starbase first with more Ogrov with more support ships.  Presently, i have not set a fleet.  I think a mixed fleet of bombers, support and capital ships may help..

I presently control 11 planets on 18 total planets

Daniel

Well, you should always kill the constructors with 2 or 3 fighter squads no matter what.

If you are fighting the Orkulus, there is good news and bad news. The good news is that it will move to attack you, so it will leave the cover of its repair bays (so don't worry about them, just make sure you're fighting far away from any defenses). The bad news is you can't outrange it.

The "pro" answer to this would be to build a lot of bombers (30+ squads) and "kite" or move your carriers around the gravity well, trying to get the starbase stuck behind other buildings in the gravity well so it can't close range with you. This takes practice though, and won't work if a large enemy fleet is present.

The other option is really to only send a bigger fleet with it. If you have Rebellion, a Raganrov titan with snipe, 10-20 Ogrovs and dozens of LRMs, bombers or whatever else you have in your fleet should take it down eventually. Keep some repair cruisers around to try and minimize loses.

Tthanks for the suggestion guys. 

I finally killed the Starbase with a bigger fleet (more Ogrovs and capital ships and better mixed flleet!!).  My main problem was the fleet.  Everythings was easier after i created a fleet where all ships works/support each others as a team instead of micro management.  Futhermore, i took my time to search and upgrade my Capital ships and build my own starbase, I have not lost a single cap ship since this create fleet feature. (Pirates was off)

I have one last question: I have 2 or 3 asteroids on the map that i can not destroy but the AI put metal/crystal extractor on them.  How could i capture those asteroid?

Daniel 

Use the colonizer frigate to capture them.

Advent:

https://www.sinsofasolarempire.wikia.com/wiki/Missionary_Vessel

TEC

https://www.sinsofasolarempire.wikia.com/wiki/Protev_Colony_Frigate

Vasari:Yes, their scout can actually crew extractors - it is considered a huge advantage in early game as an neutral extractor gets you much more than a extractor on a planet.

https://www.sinsofasolarempire.wikia.com/wiki/Jikara_Navigator

Generally, the wiki is quite helpful.

Yeah!!

I won my first SOSE game!

Goa answered this correctly. Bombers is the best bet to kill a starbase, just remember if they have fighters which the AI typically does you can't go ALL bombers or they eventually wear down you bomber fleet.

There was a section at the end of that post detailing what works. A large mixed fleet can also brute force most starbases down as you discovered. 

What kills starbases?

BOMBERS! *****
Vasari Star base ****
TEC Ogrov Torpedo Cruisers (with fighter/flak support) ***
Kortul (lvl 3+ with fighter/bomber support, against lower level star bases) **
Heavy Cruisers (works well against lower level star bases) **
LRM (works ok against lower level or deploying star bases) **
LF (works ok against deploying star bases or low level star bases with low hull) *
Advent Adjudicators (sorta, very weak and meant to attack multiple targets) *

You may be tempted to send your fleet directly against a star base. Don’t do it unless it is deploying or for the final kill! Don’t be the AI and suicide your fleet against it. Your also only helping to level up his capital ship by needlessly sacrificing LF/LRF. This also goes for your bombers, if his fighters outnumber your bombers don’t provide him the experience. Work for the upper hand first.

IMO Carriers and some flak should be your first priority against a star base. However, if they are using their defensive capabilities this may be more difficult than planned!

I think you should add LRM + Akkan with targeting. I don't know what level it has to be but if you went with a strong LRM fleet early game and you encounter a stationary starbase with a mid-level Akkan, this can allow you to avoid building mass carriers or Ogrovs, though it will be much slower.